Ignition switch and safety device



1,614 376 Jan. 11 1927- MacGLASHAN IGNITION SWITCH AND SAFETY DEVICE Filed Nov. 50, 1923 ATTORNEY 1,614,376 PATENT OFFICE.

LEE HAOGLAHAN, OF MO'JJLEY, MINNESOTA.

IGNITION SWITCH AND SAFETY DEVICE.

Application filed November 30, 1923. Serial No. 677,807.

This invention relates to a combination ignition switch and safety device and has for its primary object the construction of a device which may be manually operated and I; automatically regulated according to the oil pressure of themotor.

An object of the invention is the novel manner of constructing and associating the various parts so that the switch may be manually operated for closing the ignition circuit and as long as the motor is running and creating proper oil pressure the switch will remain closed but upon decrease of the oil pressure below a predetermined degree the switch will automatically open for stopping the engine.

A feature of my invention is the simplicit-v of construction and novel manner of associating the various parts.

Another object of the invention is the construction of an ignition switch which is automatically closed by oil pressure created as the starter operates the motor eliminating the necessity of manual operation unless so desired.

Another object of the invention is to provide a; device that is positive and unfailing in operation so as to positively prevent leaving the ignition switch closed when not in motion.

Another object of the invention is the construction of a device which will bring the ignition switch under control of oil pressurev thereby bringing thetwo most vital functions of the motor under the control of a device positive in its operation.

With these and other obiects in view the invention willbe better understood from the ,following detailed description taken in cpnnection with the accompanying drawing wherein:

The figure is a vertical sectional view ofthe device.

Again referring to the drawing illustrating one of the many constructions of my invention the numeral 1 designates a casing.

in which is arranged a flexible diaphragm 2 which divides the interior of the casing into fron't compartment 3 and rear compartment 41 The rear compartment 4 is adapted to receive a quantity of oil under pressure through the oil -pipe 5 which COlTIIIIUIIICZXQS I'- ranged in the front compartment is my novel construction of switch 6 which comprises a movable contact 7 connected. to the diaphragm, and a stationary contact 8 arranged 1n the plate 9 of insulating material which is connected to the front of the casing. A stem 10 projects from the movable contact through the plate 9 and has attached thereto an operating knob 11. The contact 7' is provided with screw threads in cooperation with the nut 12 arranged to vary the pressure of a spring 13 which constantly acts to separate thecontacts. I haveillustrated a diagrammatic view showing a portion of the ignition circuit '14. I

From the foregoing description taken in connection with the accompanying drawing it will be seen that when the knob 11 is pulled forward to pull the contacts in engagement the ignition circuit is completed so that the motor may be started. Upon starting of the motor pressure of the oil in comparement 1 will increase and extend and flex the diaphragm 2 the required degree to hold the contacts in engagement. This condition will continue to exist as long as the motor is operated and oil pressure is correct but upon lowering of the oil pressure below a predetermined degree the diaphragm will move towards normal position to expand the action of spring 13 and thus the contacts are opened for breaking the ignition switch 7 circuit and stop the motor.

It is, of cours ii to be undersdtood that the i ention ay e constructe in various o t hermfihrs and the parts associated in different relations, therefore," I do not desire to be limited in any manner except as set forth in the claim hereunto appended.

Having thus described my invention what I claim is:

An ignition switch and safety device including a casing, avdiaphragm confined in the casing and dividing the easing into front and rear compartments, a contact element operating knob carried by the stem for moving the diaphragm forwardly Within the casing to enlarge the rear compartment, said diaphragm being normally disposed in a position to bring the first mentioned contact element into contact with the second mentioned contact element by the pressure of fluid confined in the rear compartment and adapted to move in a direction to disengage the second mentioned contact element from the first mentioned contact element by action of the spring member upon decrease of the pressure of the fluid 'within the rear chamber, and means for supplying fluid to the rear compartment.

In testimony whereof I afiix my signature.

LEE J. MACGLASHAN. 

